• 천문학논총
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• 제19권1호
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• pp.11-16
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• 2004

In this review article the famous 'jet equation' in a Minkowski magnetosphere around the compact objects will be fully derived for the pedagogical purposes.

• 천문학논총
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• 제8권1호
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• pp.179-183
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• 1993

We analyze the evolution of active galactic nuclei for the decreasing accretion rate case. Our analysis is based on the unified theory of active galactic nuclei which entirely depends on the accretion rates of the central supermassive black holes. Our discussion leads us to conclude that active galactic nuclei may evolve from QSOs into the nuclei of Seyfert or radio galaxies.

• Journal of Chest Surgery
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• 제24권12호
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• pp.1225-1227
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• 1991

Pneumomediastinum and subcutaneous emphysema produced by air turbine dental drills, although widely reported in dental publications, are rarely reported in the thoracic journals. We report a case of 38-year-old man with pneumomediastinum and subcutaneous emphysema after use of a air turbine dental drill for dental extraction.

• 천문학논총
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• 제17권1호
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• pp.1-6
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• 2002

In this review article the famous 'jet equation' of the neutron stars and black holes will be fully derived for the pedagogical purposes.

• 천문학논총
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• 제4권1호
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• pp.63-70
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• 1989

스테핑모터를 이용하여 간단하면서도 안정성이 좋은 망원경 구동장치를 제작하였다. 스테핑모터의 제어 구동회로는 +5V의 단일전원으로도 정전류 구동에 가까운 효율을 얻을 수 있도록 설계되었다. 이 회로는 적은 수의 값싼 TTL IC 소자들로만 이루러져 있어 손쉽게 만들 수 있고 컴퓨터에 의한 제어가 쉽다는 강점이 있다.

• 천문학논총
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• 제26권2호
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• pp.55-70
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• 2011

Cosmological linear perturbation theory has fundamental importance in securing the current cosmological paradigm by connecting theories with observations. Here we present an explanation of the method used in relativistic cosmological perturbation theory and show the derivation of basic perturbation equations.

• 천문학논총
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• 제30권2호
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• pp.577-581
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• 2015

The main goals of the Parkes Pulsar Timing Array (PPTA) project are to 1) detect ultra-low-frequency gravitational waves, 2) improve the solar system planetary ephemeris and 3) provide a long-term, stable time standard. In this paper, we highlight the main results from the project so far and discuss our expectations for the future.

• 천문학논총
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• 제30권2호
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• pp.617-620
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• 2015

This paper presents an overview of the large international projects in which the National Astronomical Observatory of Japan is involved, namely, the Subaru Telescope, Atacama Large Millimeter/submillimeter Array, and the Thirty Meter Telescope. The last section provides a brief historical view of the international collaboration in East Asia regions over the last 20 years.

• 천문학논총
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• 제30권2호
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• pp.655-657
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• 2015

The Australia Telescope National Facility (ATNF) consists of the Parkes and Mopra radio telescopes, and the Australia Telescope Compact Array, with the first elements of the wide-field Australian Square Kilometer Array Pathfinder (ASKAP), currently being commissioned. The capabilities of these facilities are described.

• 천문학논총
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• 제34권2호
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• pp.29-30
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• 2019